Stereodivergent Michael addition of diphenylphosphite to α-nitroalkenes in the presence of squaramide-derived tertiary amines: an enantioselective organocatalytic reaction in supercritical carbon dioxide
作者:Ilya V. Kuchurov、Albert G. Nigmatov、Evgeniya V. Kryuchkova、Alexey A. Kostenko、Alexandr S. Kucherenko、Sergei G. Zlotin
DOI:10.1039/c3gc41647j
日期:——
The first “green” asymmetric organocatalytic reaction in a supercritical carbon dioxide medium was elaborated. Under the proposed conditions (100 bar, 35 °C), α-nitroalkenes enantioselectively accept diphenylphosphite in the presence of bifunctional organocatalysts bearing the tertiary amino group and the squaramide fragment to afford corresponding β-nitrophosphonates in high yields and with enantioselectivities
阐述了超临界二氧化碳介质中的第一个“绿色”不对称有机催化反应。在建议的条件下(100 bar,35°C),在带有带有叔氨基和方酸酰胺片段的双官能有机催化剂存在下,α-硝基烯烃对映选择性地接受亚磷酸二苯酯,从而以高收率和高达94的对映选择性提供相应的β-硝基膦酸酯。 %ee。通过改变催化剂结构,可以在这些条件下合成两种β-硝基膦酸酯对映异构体。证明了超临界萃取对于产物分离和催化剂回收的巨大潜力。